This PowerShell script retrieves Azure maintenance configurations, counts associated VMs, using Azure Maintenance and Resource Graph modules.

AzureMaintConfig_VMCount.ps1

# This script retrieves maintenance configurations and the count of VMs associated with each configuration
# The script uses the Azure Maintenance and Azure Resource Graph modules
# Author: Blake Drumm (blakedrumm@microsoft.com)
# Date created: May 20th, 2024
# Original location: https://gist.github.com/blakedrumm/70abcf47d0e788d91a7f277d4590f122

# Import the required module
Import-Module Az.Maintenance
Import-Module Az.ResourceGraph

# Define the subscription ID and location
$subscriptionId = (Get-AzContext).Subscription.Id
$location = 'eastus'

# Get the maintenance configurations
$maintenanceConfigurations = Get-AzResource -ResourceType 'Microsoft.Maintenance/maintenanceConfigurations'

# Initialize an array to store the results
$results = @()

# Loop through each maintenance configuration
foreach ($config in $maintenanceConfigurations) {
    # Extract the configuration name and resource ID
    $configName = $config.Name
    $configResourceId = $config.ResourceId

    # Run the KQL query to get the VM count
    $query = @"
maintenanceresources
| where ['type'] =~ "microsoft.maintenance/configurationassignments"
| where location in ( '$location' )
| where properties.maintenanceConfigurationId =~ '$configResourceId'
| distinct tostring(tolower(properties.resourceId))
"@
    $data = Search-AzGraph -Query $query

    # Create a PSObject for the current configuration and VM count
    $result = [PSCustomObject]@{
        MaintenanceConfigurationName = $configName
        MaintenanceConfigurationResourceId = $configResourceId
        vmCount = $data.Count
    }

    # Add the result to the results array
    $results += $result
}

# Output the results
$results

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